1. Field of the Invention
This application relates generally to hummingbird feeders and, in particular, to hummingbird feeders having solar-powered internal illumination of an aqueous nutrient solution for feeding at night.
2. Description of Related Art
People achieve pleasure from watching hummingbirds fly. Consequently, people who live in areas inhabited by hummingbirds often encourage their presence via the use of hummingbird feeders, the sugar-laden solution within giving the birds extra energy to hunt their main food of small insects. Hummingbird feeders differ from conventional seed type bird feeders in that they provide a liquid solution of granulated sugar and water as opposed to dry feed.
There are basically four common types or configurations of hummingbird feeders.
A first type utilizes a tube extending from the bottom of a bottle such as is shown in U.S. Pat. No. 4,558,662. The aforementioned type of hummingbird feeder exposes the solution which the hummingbirds drink at the bottom of the tube while in flight.
A second type utilizes a tube extending from above and to the side of a reservoir, often resembling a flower as disclosed in U.S. Design Pat. No. D454,669.
A third type of hummingbird feeder comprises a bottle or jar, the neck of which is located inside a covered bowl. The aforementioned type of hummingbird feeder is disclosed in U.S. Pat. Nos. 5,682,835 and 3,720,184. This type of feeder utilizes an internal vacuum to meter the flow of the solution of the bottle according to demand from the hummingbirds.
A fourth type of feeder is a pan or shallow bowl with a cover as disclosed in U.S. Pat. No. 5,454,348.
Solar energy systems that collect solar energy and convert it into electrical energy have been around for many years. However, only recently have these solar energy systems been developed to the point where they are small enough, efficient enough, and economical enough, to allow their widespread use in small electrical devices. One use of these small solar energy systems is to recharge rechargeable batteries in small household devices such as outdoor landscaping lighting. The rechargeable batteries provide power to illuminate the lighting elements during darkness, and the solar energy system collects and converts solar energy and recharges the rechargeable batteries during daylight. Another use is to illuminate bird seed feeders.
Solar illuminated bird feeders are known in the prior art and disclosed, for example, in U.S. Pat. Nos. 6,830,009, 6,901,882 and 7,017,521. Most current embodiments of solar lighted bird feeders have illumination sources outside the bird seed reservoir usually shining downward to illuminate the perch from above or illuminate part of the food reservoir from above. Some current embodiments of solar lighted bird feeders use light impermeable solid type feed. All current embodiments of solar lighted bird feeders are designed for using light-impermeable seed type feed. Some of the bird seed may also be illuminated but since bird seed is not light transmissive, only the region proximate to a surface of the food reservoir of a filled solar birdfeeder is illuminated. Thus the prior art does not disclose a bird feeder that illuminates throughout the food reservoir. Further, the seed reservoirs are usually a smooth sided glass or plastic material which reflects a substantial amount of light off the reservoir surface due to the low angle of incidence of the light source in relation the angle of the surface of the food reservoir. Thus there is a need for a solar lighted bird feeder that illuminates both a food reservoir and most of the food source therein. The present invention satisfies this need.
It is well known that a hummingbird's usage pattern may be broken if the feeder is empty. Accordingly, for best results and for the welfare of migrating hummingbirds, there is a need to keep fresh feeding solution for at least one week after the last bird has been seen feeding. The average hummingbird can consume up to 50% of its body weight in liquid food daily. The owner of a hummingbird feeder may enjoy watching the hummingbirds feed early during the day before they travel to their work. However, many people return home from work after dark. On an evening when a user cannot readily determine the solution level in the feeder and thus if the feeder needs refilling, the need is not readily apparent in the dark. Attempts to solve this problem have generally been based around simply increasing the food reservoir size but such an approach is not always practical as the solution has a tendency to spoil rapidly. The present invention overcomes such a problem by illuminating the liquid food supply so that it is visible from a distance at night. Thus there is a need for solar powered illuminated hummingbird feeder.
As noted above, it would be useful to know when the hummingbird feeder is approaching an empty state. Utilizing the change in weight of the declining food source in the feeder is a useful method of determining an approaching empty state before the feeder is empty. With seed based feeders, the various birdseed types have varying volume-to-weight ratios so it may be difficult to establish a universal “almost empty weight” for a seed feeder. Unlike seed used in solid birdseed feeders, the liquid food source used in hummingbird feeders has a relatively constant weight to volume relationship. Accordingly, it is relatively straightforward to establish a weight of the hummingbird feeder when it is not completely empty but is almost empty of the liquid food source. In the preferred embodiment of the present invention this problem is solved by the hummingbird feeder providing an alert system when the hummingbird feeder needs refilling. In the preferred embodiment, there is a visual alert system that is visible in low light conditions. Alternatively or additionally, there may be an acoustic alert system or the feeder may provide an alert system using radio frequency communication to a remote receiver unit.
Some hummingbirds commence feeding as early as 30 minutes before sunrise. However, it is dark at that time and thus not suitable for the owner of a feeder to view the hummingbird feeding. One embodiment of the present invention partially ameliorates such a problem by illuminating part of the feeder.
Some bird feeders use a phosphorescent glass food reservoir to provide some low level of illumination for a few hours at dusk, however, such a method of illumination does not visibly and clearly illuminate a liquid feed solution. This problem can be overcome by internally illuminating the light transmissive glass food reservoir from within using a high efficiency light emitting diode (LED). Then at night the liquid food solution is visible. The LED requires electrical power to operate. One method of powering is electrical cabling running from a main power supply near a house to the feeder. This is often inconvenient as the feeder may be located at an impractical distance from an electrical outlet. Accordingly, the present invention overcomes this problem by powering the LED by batteries of a common size and type. Alkaline batteries are economical but require frequent replacement which may be inconvenient for the owner. The present invention overcomes this problem by providing batteries which are recharged by a solar charging system thus removing the need for regular battery replacement.
Unlike seed type bird feeders, hummingbird feeders use a liquid food solution rich in sugar. Accordingly, the solution can spoil very easily and hummingbirds will not consume spoiled feed solution. Most feeders should be cleaned bi-weekly. This usually necessitates immersion of the solution contacting parts in water. Attempts have been made to circumvent this problem by making disposable hummingbird feeders but this is uneconomical and wasteful. Accordingly, frequent submersion washing is normally required for hummingbird feeders. One problem that exists with solar illuminated hummingbird feeders is the electrical parts that create the solar illumination are not usually suitable for water immersion. Accordingly, the present invention is designed such that the solar and water sensitive electrical parts are easily removable from the parts that require frequent washing and cleaning.
Most solar garden lights and solar birdfeeders use solar panels located on an upward facing surface of an upper canopy or housing because they utilize photovoltaic silicon solar panels made using a crystalline structure. This type of solar panel needs direct sunlight to charge normally and so the usual best orientation for receiving direct sunlight is a horizontally oriented solar panel located on an upper surface of the canopy or housing. However, in many situations it may be preferable to hang a bird feeder from a tree branch for support and to attract the birds to a more natural feeding environment. Unfortunately, the foliage or the branch itself may partially restrict the amount of sunlight or light energy from reaching the top of the bird feeder or lighting device and thus the solar panel. As a result, solar panels on the top of the light device or birdfeeder do not receive adequate sunlight to fully charge their batteries and fail to provide illumination of adequate duration. An embodiment of the present invention overcomes this problem by utilizing back-to-back thin-film amorphous silicon solar panels suspended vertically below the hummingbird feeder or solar light where it is low enough to be out of the way of the light blocking of foliage and can use ambient light to charge the solar panels instead of requiring direct sunlight.
Also, trees are usually planted and located a safe distance away from house and window structures to prevent damage from falling tree branches and migration of wood damaging insects such as termites or other pests that may use the tree structure as a means of invading the house structure. In addition, in wildfire prone areas, trees in close vicinity to homes are usually cut to provide a fire break or buffer in the event of a wildfire. An embodiment of the present invention overcomes these problems by providing a self supporting solar illuminated hummingbird feeder where it may be located in a sunny location away from trees but close to houses where the illuminated hummingbird feeder may be viewed from inside the home at night.
The manufacture of a solar illuminated garden light or solar bird feeder involves disparate manufacturing techniques. The housings are often made from a variety of materials including stamped metals, cast metals, thermoplastics and glass. The manufacturing facilities and environment for these materials is dramatically different from the manufacturing environment required to produce the electronics assemblies that form the solar charging and lighting functions. As a result the electronics assembly is often conducted remotely from activities such as die-casting of metal housings, some times in different countries. This means that the housings are usually transported to the electronics assembly locations. Unfortunately, the housings are the bulkiest and most expensive parts to send by freight but this has been the practice because the solar and electronic parts are integrally assembled into the housings. Further, many lighting and birdfeeder housings have different shaped and sloped regions on their top portions which makes some designs not suitable for locating solar panels thereon and those designs are not produced as solar products. Further, a factory may produce multiple housing designs which need to have solar panels incorporated therein. This results in some designs not being produced with solar functions and results in many different shaped and sized solar panel components that must be ordered from the solar panel producers. An embodiment of the present invention overcomes these problems by combining all the electronic solar charging, power storing, control and illumination components into an easily assembled module that may be incorporated into most hanging light fixtures and attached in a final assembly operation at any suitable location without any specialized equipment.
The size of a solar panel in most commonly sold landscape lights is usually sized in capacity to fully charge a power source in six to eight hours of direct sunlight. If the panel is sized with a larger charging capacity, the battery may be fully charged earlier and then the extra power generated by the panel is wasted. If the panel is sized with a smaller charging capacity, the battery may not be fully charged and might not illuminate the light source connected to the battery for the duration of time the light source was intended to illuminate. Since the solar panel is a major cost component of a solar landscape light, manufacturers have a problem in determining an optimal charging capacity of solar panel that finds a balance between insufficient operating hours with a lower cost i.e. and expensive wasted solar power generation.
Further, there are factors that are outside the control of the manufacturer of the solar light that affect the number of daily hours and strength of direct sunlight received by the solar panel. These include, the latitude of the light installation, the cloudy density and coverage, the season, and local shading conditions including structures, plants and trees that may block direct sunlight from reaching the solar panels for some period of time. Accordingly, there are situations where the solar light may not be fully charging the battery when located at its installed location by the user. Many solar landscape lights are sold in a convenience set with 4, 6, or more lights in a single retail package. When installed, in some situations, for example, where a plurality of solar landscape lights have been installed in a garden, there may be some light fixtures that are receiving adequate sunlight and some that are receiving inadequate sunlight. Further, as the seasons change some installed lights may not be receiving sufficient light for the solar panel to fully charge the battery. One embodiment of the present invention overcomes part of these performance problems utilizing a suspended releasably attachable vertically oriented booster solar panel to provide additional charging capacity where and when required.